Damage Modle And Damage Assessment For K8 Single-layer Reticulated Domes Under Exterior Blast Load

Reticulated dome is often considered as a landmark building of a region and are quite probable to become the target of terrorist activities. Once the structure callapse for terrorist attacks, which would cause grave losses of life and property. Therefore, it is of great importance to investigate the dynamic response, failure mode, failure mechanism and damage assessment method of reticulated dome under blast loading.Long-span reticulated dome are typically more complicated than building structures, which makes it challenging to carry out numerical simulations to describe the dynamic response of these structures to blast loading. Here we discuss four numerical simulation approaches; i.e., the conventional weapons effects blast-loading model(CONWEP), the arbitrary Lagrange–Euler(ALE) algorithm, coupled CONWEP–ALE simulations, and the particle blast method(PBM). All of these are finite element method(FEM) approaches, and were implemented using ANSYS/LS-DYNA. Available experimental data were modeled to validate the accuracy of these four methods. FEM models were set up using these four methods to investigate the dynamic response of a Kiewitt-8 single-layer reticulated dome with a span of 60 m to blast loading with and without a blast wall. We compare the dynamic response and the CPU times, and find that CONWEP is the most suitable method to simulate reticulated dome in response to free air explosion; PBMis more efficient than ALE and has wide applicability. Although the results of PBM obviously deviate from these of ALE for the large scaled distance, PBM may be the most potential suitable method for all kinds of blast loading with the improvement of numerical technology.The influence of standoff distance, charge weight, rise span ratio, span and roof loading on the response of failure state was studied by using CONWEP algorithm. The results show that for smaller rise span ratio and larger span, the anti-detonation performance of reticulated dome is better. Although the load capacity of reticulated dome with large span and large roof loading is better, the plastic development degree and material utilization is small at failure state. According to the characteristic response of abundant single-layer reticulated domes at different state, the damage mode indicating the damage level of the reti culated dome was fitted. The strength failure criterion was proposed for distinguishing the ultimate load. The damage index corresponds to the physical phenomenon at different damage level, which makes the strength failure criterion has definite physical m eaning.The pressure-impulse(P-I) diagram was used to evaluate the damage degree of reticulated dome under blast loading. Based on CONWEP algorithm, a new numerical method to generate P-I diagram for reticulated dome was proposed. The P-I diagram of typical reticulated dome was generated and the characteristic was discussed.